Medicine

Lesson 1

Lesson 1

 

Symptoms of Disorders of the Genitourinary Tract

 

In the workup of any patient, the history is of paramount importance; this is particularly true in urol­ogy. It will be necessary to discuss here only those urologic symptoms that are apt to be brought to the physician's attention by the patient. It is important to know not only whether the disease is acute or chronic but also whether it is recurrent, since recurring symp­toms may represent acute exacerbations of chronic disease.

 

                                        

 

LOCAL & REFERRED PAIN

Two types of pain have their origins in the genitourinary organs: local and referred. The latter is especially common.

Local pain is felt in or near the involved organ. Thus, the pain from a diseased kidney (T10-12, LI) is felt in the costovertebral angle and in the flank in the region of and below the 12th rib. Pain from an in­flamed testicle is felt in the gonad itself.

 

                 

                                               Palpation of the kidney

 

 

 

 

             

 

                                               Palpation of the kidney

 

Referred pain originates in a diseased organ but is felt at some distance from that organ. The ureteral colic caused by a stone in the upper ureter may be associated with severe pain in the ipsilateral testicle; this is explained by the common innervation of these 2 structures (T 11-12). A stone in the lower ureter may cause pain referred to the scrotal wall; in this instance, the testis itself is not hyperesthetic. The burning pain with voiding that accompanies acute cystitis is felt in the distal urethra in the female or in the glandular urethra in the male (S2-3).

Abnormalities of a urologic organ can also cause pain in any other organ (eg, astrointestinal, gyneco­logic) that has a sensory nerve supply common to both.

Kidney Pain       

Typical renal pain is usually felt as a dull and constant ache in the costovertebral angle just lateral to the sacrospinalis muscle and just below the 12th rib. This pain often spreads along the subcostal area toward the umbilicus or lower abdominal quadrant. It may be expected in those renal diseases that cause sudden distention of the renal capsule. Acute pyelonephritis (with its sudden edema) and acute ureteral obstruction (with its sudden renal back pressure) both cause this typical pain. It should be pointed out, however, that many urologic renal diseases are painless because their progression is so slow that sudden capsular distention does not occur. Such diseases include cancer, chronic pyelonephritis, staghorn calculus, tuberculosis, polycystic kidney, and hydronephrosis due to mild ureteral obstruction.

 

Pseudorenal Pain (Radiculitis)

Mechanical derangements of the costovertebral or costotransverse joints can cause irritation or pres­sure on the costal nerves. Disorders of this sort are common in the cervical and thoracic areas, but the most common sites are T10—12. Irritation of these nerves causes costovertebral pain, often with radiation into the ipsilateral lower abdominal quadrant. The pain is positional in nature.

Its first onset is usually quite acute, following the lifting of a heavy object, a blow to the costovertebral area, or a fall on the buttocks from a height. The pain is usually absent on arising from bed but is apt to increase as the day wears on. It is exacerbated by heavy physical work and is usually increased during an au­tomobile trip over a rough road. It is apt to awaken the patient when a certain position is assumed (eg, lying on the right side) and is relieved by a change of position. Radiculitis may mimic ureteral colic or renal pain. True renal pain is seldgm affected by movements of the spine.

Ureteral Pain

Ureteral pain is typically stimulated by acute obstruction (passage of a stone or a blood clot). In this instance, there is back pain from capsular distention combined with severe colicky pain (due to renal pelvic and ureteral muscle spasm) that radiates from the cos­tovertebral angle down toward the lower anterior ab­dominal quadrant, along the course of the ureter. In men, it may also be felt in the bladder, scrotum, or testicle. In women, it may radiate into the vulva. The severity and colicky nature of this pain are caused by the hyperperistalsis and spasm of this smooth muscle organ as it attempts to rid itself of a foreign body or to overcome obstruction. It should be remembered that radiculitis may mimic ureteral pain.

The physician may be able to judge the position of a ureteral stone by the history of pain and the site of referral. If the stone is lodged in the upper ureter, the pain radiates to the testicle, since the nerve supply of this organ is similar to that of the kidney and upper ureter (Tl1-12). With stones in the mid portion of the ureter on the right side, the pain is referred to McBurney's point and may therefore simulate appendicitis; on the left side, it may resemble diverticulitis or other diseases of the descending or sigmoid colon (T12, LI). As the stone approaches the bladder, inflammation and edema of the ureteral orifice ensue, and symptoms of vesical irritability may occur. It is important to realize, however, that in mild ureteral obstruction, as seen in the congenital stenoses, there is usually no pain, either renal or ureteral.

Vesical Pain              

The overdistended bladder of the patient in acute urinary retention will cause agonizing pain in the su-prapubic area. Other than this, however, constant suprapubic pain not related to the act of urination is usually not of urologic origin. The relatively uncommon interstitial cystitis and vesical ulceration caused by tuberculosis or schistosomiasis may cause suprapubic discomfort (usually relieved by urination) when the bladder becomes full.

The patient in chronic urinary retention due to bladder neck obstruction or neurogenic bladder may experience little or no suprapubic discomfort even though the bladder reaches the level of the umbilicus.

The most common cause of bladder pain is infec­tion; the pain is usually not felt over the bladder but is referred to the distal urethra and is related to the act of urination. Terminal dysuria may be severe.

 

Prostatic Pain           

Direct pain from the prostate gland is not com­mon. Occasionally, when the prostate is acutely in­flamed, the patient may feel a vague discomfort or fullness in the perineal or rectal area (S2—4). Lumbosacral backache is occasionally experienced as re­ferred pain from the prostate but is not a common symptom of prostatitis. Inflammation of the gland may cause symptoms of cystitis.

Prostate pain is any pain or discomfort of the prostate gland. The prostate gland wraps around the tube that transports urine out of the bladder and is involved in the production of semen. Prostate pain can occur as a result of a number of diseases or disorders.

 It is very common for the prostate gland to become enlarged as a man ages. An enlarged prostate is also known as benign prostatic hyperplasia (BPH), which is generally not associated with any prostate pain. However, an enlarged prostate can cause problems with urination.

 

 Another reason for prostate pain is prostatitis, an infection of the prostate that is often caused by bacteria. Symptoms of prostatitis may vary from person to person, but general symptoms include burning with urination, the inability to empty the bladder completely, and painful urination.

 

 The presence of a cyst or abscess in the prostate can also cause prostate pain. A cyst is a benign sac that contains fluid, air, or another material. An abscess is a collection of pus that causes swelling and inflammation. Prostate pain can sometimes be associated with advanced prostate cancer.

 

 Prostate pain that is related to acute prostatitis can be life threatening.

Testicular Pain

Testicular pain due to trauma, mumps, or torsion of the spermatic cord is very severe and is felt locally, although there may be some radiation of the discomfort along the spermatic cord into the lower abdomen. It may involve the costovertebral area as well. Uninfected hydrocele, spermatocele, and tumor of the testis do not commonly cause pain.

 

  Varicocele

 

 

Varicocele or varicose seal, is an abnormal enlargement of the pampiniform venous plexus in the scrotum. This plexus of veins drains the testicles. The testicular blood vessels originate in the abdomen and course down through the inguinal canal as part of the spermatic cord on their way to the testis. Upward flow of blood in the veins is ensured by small one-way valves that prevent backflow. Defective valves, or compression of the vein by a nearby structure, can cause dilatation of the testicular veins near the testis, leading to the formation of a varicocele.

A varicocele may cause a dull ache in the testicle that is increased after heavy exercise. At times, the first symptom of an early indi­rect inguinal hernia may be testicular pain (referred). Pain from a stone in the upper ureter may be referred to the testicle.

 

Epididymal Pain

Acute infection of the epididymis is the only painful disease of this organ and is quite common. Some degree of neighborhood inflammatory reaction involves the adjacent testis as well, further aggravating the discomfort. In the early stages of epididymitis, pain may first be felt in the groin or lower abdominal quadrant. (If on the right side, it may simulate appen­dicitis.) This may be a referred type of pain but can be secondary to associated inflammation of the vas defe-rens. The discomfort associated with epididymitis may reach the costal angle and mimic ureteral stone.

Back &Leg Pain

Pain low in the back and radiating down one or both legs, especially when associated with symptoms of vesical neck obstruction, suggests metastases to the pelvic bones from cancer of the prostate.

 

 

SYMPTOMS RELATED TO THE ACT OF URINATION

Many conditions cause symptoms of ''cystitis''. These include infections of the bladder, vesical in­flammation due to chemical or x-ray radiation reac­tions, interstitial cystitis, prostatitis, senile urethritis, psychoneurosis, torsion or rupture of an ovarian cyst, and foreign bodies in the bladder. Often, however, the patient with chronic cystitis notices no symptoms of vesical irritability. In children who have taken bubble baths, symptoms resembling cystitis may be noted secondary to the resulting urethritis.

Frequency, Nocturia, & Urgency

The normal capacity of the bladder is about 400 mL. Frequency may be caused by residual urine, which decreases the functional capacity of the organ. When the mucosa, submucosa, and even the mus-cularis become inflamed (eg, infection, foreign body, stones, tumor), the capacity of the bladder decreases sharply. This decrease is due to 2 factors: the pain resulting from even mild stretching of the bladder and the loss of bladder elasticity resulting from inflamma­tory edema. When the bladder is normal, urination can be delayed if circumstances require it, but this is not so in acute cystitis. Once the diminished bladder capacity is reached, any further distention may be agonizing, and the patient may actually urinate in­voluntarily if voiding does not occur immediately. During very severe acute infections, the desire to urinate may be constant, and each voiding may pro­duce only a few milliliters of urine. Day frequency without nocturia and acute or chronic frequency lasting only a few hours suggest nervous tension.

Diseases that cause fibrosis of the bladder are accompanied by frequency of urination. Examples of such diseases are tuberculosis, interstitial cystitis, and schistosomiasis. The presence of stones or foreign bodies causes vesical irritability, but secondary infec­tion is almost always present.

What is nocturia?

Nocturia is a condition in which you wake up during the night because you have to urinate. This condition becomes more common as people age and occurs in both men and women, sometimes for different reasons.

What are the symptoms of nocturia?

 

Normally, you should be able to sleep six to eight hours during the night without having to get up to go to the bathroom. People who have nocturia wake up more than once a night to urinate. This can cause disruptions in a normal sleep cycle.

 

Nocturia may result from several different causes:

You produce a great deal of urine (more than 2 liters) a day (polyuria)

Your body produces a large volume of urine while you sleep (nocturnal polyuria)

You produce more urine at night than your bladder is able to hold (low nocturnal bladder capacity). This causes you to wake up at night because you need to empty your bladder.

a combination of nocturnal polyuria and low nocturnal bladder capacity (mixed nocturia)

Poor sleep – some people who have poor sleep and awaken frequently will go to the bathroom whenever they awaken. Typically in these cases, it is not the need to void that awakens them.

Nocturia is often a symptom of renal disease related to a decrease in the functioning renal paren­chyma with loss of concentrating power. Nocturia may occur in the absence of disease in persons who drink excessive amounts of fluids in the late evening. Coffee and alcoholic beverages, because of their specific di­uretic effect, often produce nocturia if consumed just before bedtime. In older people who are ambulatory, some fluid retention may develop secondary to mild heart failure or varicose veins. With recumbency at night, this fluid is mobilized, leading to nocturia in these patients.

Causes of nocturnal polyuria

Congestive heart failure

Edema of lower extremities (swelling of the legs)

Sleeping disorders such as obstructive sleep apnea (breathing is interrupted or stops many times during sleep)

Certain drugs, including diuretics (water pills), cardiac glycosides, demeclocycline, lithium, methoxyflurane, phenytoin, propoxyphene, and excessive vitamin D

Drinking too much fluid before bedtime, especially coffee, caffeinated beverages, or alcohol

A very low or very high urine pH can irritate the bladder and cause frequency of urination. In chronic obstructive pulmonary disease, the PaCO2 is elevated. Compensation requires increased urinary excretion of chloride, leading to a low pH (Farcon and Morales, 1972). With hyperventilation, the urine becomes strongly alkaline.

Burning Upon Urination

This is common in acute cystitis and prostatitis. In men, it is usually felt in the distal urethra just proximal to or in the glans. In women, it is ordinarily referred to the urethra. It is important to remember that it is rarely felt in the suprapubic area. This burning sensation occurs in association with the act of urination, al­though it may be more marked at the beginning of, during, at the end of, or occasionally after urination. It may be very severe. Vague pain in the urethra not associated with the act of voiding is usually not caused by urinary system disease. In men, it is apt to be a psychosexual symptom; in women, however, it may occasionally be caused by chronic urethritis.

Enuresis

Strictly speaking, enuresis means bedwetting at night. It is physiologic during the first 2 or 3 years of life but becomes troublesome, particularly to parents, after that age. It may be functional or secondary to delayed neuromuscular maturation of the urethrovesi-cal component, but it may present as a symptom of organic disease (eg, infection, distal urethral stenosis I in girls, posterior urethral valves in boys, neurogenic I bladder). If, however, wetting occurs also during the I daytime or if there are other urinary symptoms—or if the enuresis persists beyond age 6 or 7—urologic investigation is essential. In adult life, enuresis may be replaced by nocturia for which no organic basis can be found.

Symptoms of Prostatic Obstruction

A. Hesitancy and Straining: Hesitancy in initi­ating the urinary stream is one of the early symptoms of an enlarged prostate. As the degree of obstruction increases, hesitancy is prolonged; the patient may have to strain in order to initiate urination.

B. Loss of Force and Decrease of Caliber of the Stream: Progressive loss of force and caliber of the I urinary stream is noted as urethral resistance increases despite the generation of increased intravesical pres­sure.

C. Terminal Dribbling: This becomes more and more noticeable as obstruction progresses and is a most distressing symptom.

D. Acute Urinary Retention: Sudden inability to urinate may supervene. The patient experiences increasingly agonizing suprapubic pain associated with severe urgency and may dribble only small amounts of urine.

Signs and symptoms

Urinary retention is characterised by poor urinary stream with intermittent flow, straining, a sense of incomplete voiding, and hesitancy (a delay between trying to urinate and the flow actually beginning). As the bladder remains full, it may lead to incontinence, nocturia (need to urinate at night), and high frequency. Acute retention causing complete anuria is a medical emergency, as the bladder can stretch to enormous sizes and possibly tear if not dealt with quickly. If the bladder distends enough it becomes painful. The increase in bladder pressure can also prevent urine from entering the ureters or even cause urine to pass back up the ureters and get into the kidneys, causing hydronephrosis, and possibly pyonephrosis, kidney failure, and sepsis. A person should go straight to an emergency department or A&E service as soon as possible if unable to urinate with a painfully full bladder.

 

      

 

                                       Acute Urinary Retention

 

 

   USI acute retention

 

Causes

In the bladder

Detrusor sphincter dyssynergia

Neurogenic bladder (commonly pelvic splanchic nerve damage, cauda equina syndrome, descending cortical fibers lesion, pontine micturation or storage center lesions, demyelinating diseases or Parkinson's disease)

Iatrogenic (caused by medical treatment/procedure) scarring of the bladder neck (commonly from removal of indwelling catheters or cystoscopy operations)

Damage to the bladder

In the prostate

Benign prostatic hyperplasia

Prostate cancer and other pelvic malignancies

Prostatitis

Penile urethra

Congenital urethral valves

Phimosis or pinhole meatus

Circumcision

Obstruction in the urethra, for example a metastasis or a precipitated pseudogout crystal in the urine

STD lesions (gonorrhoea causes numerous strictures, leading to a "rosary bead" appearance, whereas chlamydia usually causes a single stricture)

Other

Tethered spinal cord syndrome

Paruresis ("shy bladder syndrome")- in extreme cases, urinary retention can result

Consumption of some psychoactive substances, mainly stimulants, such as MDMA and amphetamine.

Use of NSAIDs or drugs with anticholinergic properties.

Stones or metastases can theoretically appear anywhere along the urinary tract, but vary in frequency depending on anatomy

Muscarinic antagonist such as Atropine and Scopolamine

 

Paruresis, inability to urinate in the presence of others (such as in a public restroom), may also be classified as a type of urinary retention, although it is psychological rather than biological.

Treatment

In acute urinary retention, urinary catheterization, placement of a prostatic stent or suprapubic cystostomy relieves the retention. In the longer term, treatment depends on the cause. BPH may respond to alpha blocker and 5-alpha-reductase inhibitor therapy, or surgically with prostatectomy or transurethral resection of the prostate (TURP). Older patients with ongoing problems may require continued intermittent self catheterization. 5-alpha-reductase inhibitor increase the chance of normal urination following catheter removal.

 

E. Chronic Urinary Retention: This may cause little discomfort to the patient even though there is great hesitancy in starting the stream and marked re­duction of its force and caliber. Constant dribbling of urine (paradoxic incontinence) may be experienced. It I may be likened to water pouring over a dam.

F. Interruption of the Urinary Stream: Inter­ruption may be abrupt and accompanied by severe pain radiating down the urethra. This type of reaction strongly suggests the complication of vesical calculus.

G. Sense of Residual Urine: The patient often feels that urine is still in the bladder even after urina­tion has been completed.

H. Cystitis: Recurring episodes of acute cystitis suggest the presence of residual urine.

Symptoms of Urethral Obstruction

In males, the combination of a slow and bifur­cated stream suggests urethral stricture. A slow, weak stream in a male infant or little boy is compatible with posterior urethral valves or congenital urethral stric­ture.

Little girls with or without urinary infection may have a slow, hesitant, or interrupted stream. This should suggest involuntary spasm of the periurethral striated musculature secondary to distal urethral stenosis. Some women complain of constant impairment of urinary flow, in which case the possibility of urethral stricture should be investigated. Often, however, careful questioning will reveal that some voidings are slow, whereas others are quite free. This is compatible with periodic periurethral muscle spasm on a psychogenic basis.

Incontinence

There are many reasons for incontinence. The history often gives a clue to its cause.

A. True Incontinence: The patient may lose urine without warning; this may be a constant or periodic symptom. The more obvious causes include exstrophy of the bladder, epispadias, vesicovaginal fistula, and ectopic ureteral orifice. Injury to the ure­thral smooth muscle sphincters may occur during pros­tatectomy or childbirth. Congenital or acquired neurogenic diseases may lead to dysfunction of the bladder and incontinence.

 

 

B. Stress Incontinence:

 

                                   

 

 

 

 

 When slight weakness of the sphincteric mechanisms is present, urine may be lost in association with physical strain (eg, coughing, laughing, rising from a chair). This is common with vesical neurogenic disease. The patient stays dry while lying in bed.

 

 

 

 

 

 

C. Urge Incontinence: This type of urgency may be so precipitate and severe that there is involuntary loss of urine. Urge incontinence not infrequently oc­curs with acute cystitis, particularly in women, since they seem to have relatively poor anatomic sphincters. Urge incontinence is a common symptom of an upper motor neuron lesion. It is often seen also in tense, anxious women even in the absence of infection.

 

              

 

 

 

D. Paradoxic (Overflow or False) Inconti­nence: This is loss of urine due to chronic urinary retention or secondary to a flaccid bladder. The in-travesical pressure finally equals the urethral resis­tance; urine then constantly dribbles forth.

 

 

 

 

 

Oliguria & Anuria          

Anuria is the complete absence of urine production. Oliguria is present when less than 30 ml of urine is excreted in twenty four hours. Anuria may occur due to Prerenal, renal and Postrenal causes.

 

The Prerenal causes of anuria include hypovolemia, sepsis, cardiogenic shock and hypoxia. Hypovolemia may result from inadequate fluid intake or its excessive loss from the body. Blood loss caused by injury and other causes also leads to hypovolemia. Cardiogenic shock due to myocardial infarction may result in low cardiac output and poorly oxygenated blood.

 

                                        

 

 

The renal causes are mostly due to damage or ischemia of the glomeruli and renal tubules. The main causes are incompatible blood transfusion, severe shock for a long period, myoglobinuria, the presence of myoglobin in the urine is associated with crush syndrome after major trauma; disseminated intravascular coagulation usually follows major sepsis or massive blood transfusion and may occur postpartum. Certain, nephrotoxic agents like contrast media for angiography, and toxins of eclampsia may lead to anuria.

 

 

 

 

Postrenal anuria is usually due to obstruction to flow the urine through the lower urinary tract. Calculus disease is a common cause of acute obstruction leading to anuria, e.g. the stone obstructing the ureter of the only functioning kidney.

 

 

The problem cause of anuria should be established. The bladder is catheterized if a voided sample cannot be obtained. Urine is checked for specific gravity, presence of casts (implying a renal cause), urine is sent for culture and microscopy. Any obvious prerenal cause is looked into; what drugs have been given recently? Is there a uretric obstruction?

 

The renal anuria due to acute tubular necrosis can be reversible and may progress through three recognizable phases: (1) phase of Oliguria; (2) phase of dieresis; and (3) phase of recovery.

 

During the Oliguria phase, excess fluid loads must be avoided and fluid intake restricted to match the reduced output plus insensible losses. Abnormal losses (vomiting, nasogastric suction, diarrhoea) will need to be monitored and replaced.

Prerenal causes

Decreased cardiac output

Hypovolemia

Peripheral vasodilatation

Reno vascular obstruction

Severe vasoconstriction

 

Internal Cause

Acute tubular necrosis

Cortical necrosis

Glomerulonephritis

Papillary necrosis

Renal vascular occlusion

Vacuities

 

Postrenal Causes

Bladder obstruction

Ureteral obstruction

Urethral obstruction

Inspect and palpate the abdomen for asymmetry, distention, or bulging.

Inspect the flank area for edema or erythema, and percuss and palpate the bladder.

Assess a urine sample for cloudiness and foul odor.

 

Pneumaturia

The passage of gas in the urine almost always means that there is a fistula between the urinary tract and the bowel. This occurs most commonly in the bladder or urethra but may be seen also in the ureter or renal pelvis. Carcinoma of the sigmoid colon, diver-ticulitis with abscess formation, regional enteritis, and trauma cause most vesical fistulas. Congenital anomalies account for most urethroenteric fistulas. Certain bacteria, by the process of fermentation, may rarely liberate gas.

Cloudy Urine

Patients often complain of cloudy urine, but it is most often cloudy merely because it is alkaline; this causes precipitation of phosphate. Chyluria is a rare cause of cloudy urine. A properly performed urinalysis will reveal the cause of cloudiness.

 

 

Bloody Urine                               Hematuria

 

Hematuria is a danger signal that cannot be ig­nored. It is important to know whether urination is painful or not, whether the hematuria is associated with symptoms of vesical irritability, and whether blood is seen in all or only a portion of the urinary stream. Some individuals (particularly if they are anemic) will pass red urine after eating beets or taking laxatives containing phenolphthalein, in which case the urine is translucent rather than opaque and contains no red cells. Because of the wide use of rhodamine B as a coloring agent in cookies, cakes, cold drinks, and fruit juices, children commonly pass red urine after the ingestion of these foods. This is the so-called Monday morning disorder. The hemoglobinuria that occurs as a feature of the hemolytic syndromes may also cause the urine to be red.

A.                        Bloody Urine in Relation to Symptoms and Diseases: Hematuria associated with renal colic suggests ureteral stone, although a clot from a bleeding renal tumor can cause the same type of pain.

 

                                  Hematuria   

 

Hematuria is not uncommonly associated with nonspecific, tuberculous, or schistosomal infection of the bladder; The bleeding is often terminal (bladder neck or prostate), although it may be present through­out urination (vesical or upper tract). Stone in the bladder often causes hematuria, but infection is usually present, and there are symptoms of bladder neck obstruction, neurogenic bladder, or cystocele. When a tumor of the bladder ulcerates, it is often complicated by infection and bleeding. Thus, symptoms of cystitis and hematuria are also compatible with tumors.

Dilated veins may develop at the bladder neck secondary to enlargement of the prostate. These may rupture when the patient strains to urinate.

Hematuria without other symptoms ("silent") must be regarded as a symptom of tumor of the bladder or kidney until proved otherwise. It is usually intermit­tent; bleeding may not recur for months. Complacency because the bleeding stops spontaneously must be condemned. Less common causes of silent hematuria are staghorn calculus, polycystic kidneys, solitary renal cyst, sickle cell disease, and hydronephrosis. Painless bleeding is common with acute glomerulonephritis. Recurrent bleeding is occasionally seen in children suffering from focal glomerulitis.

 

 

 

 

Hematuria can also be the first sign of intrinsic renal disease or malignancy. Blood can come from the kidney, GU tract, or urethra. More serious causes of hematuria are diverse, and include the following:

renal causes

-IgA nephropathy

-Alport's syndrome

-focal segmental glomerulosclerosis

-membroproiferative glomerulosclerosis

-post-infectious glomerulonephritis

-polycystic kidney disease

-papillary necrosis

urological causes

-benign prostatic hypertrophy

-urothelial tumours

-renal/bladder stones      

systemic causes

-Henoch-Schonlein purpura (HSP)

-systemic lupus erythmatosus (SLE)

-bacterial endocarditis

 

 

 

Richie and Kerr (1979) remind us that white pa­tients can have sickle cell trait. Joggers frequently develop transient proteinuria and gross or microscopic hematuria (Boileau et al, 1980).

B. Time of Hematuria: Learning whether the hematuria is partial (initial, terminal) or total (present throughout urination) is often of help in identifying the site of bleeding. Initial hematuria suggests an anterior urethral lesion (eg, urethritis, stricture, meatal stenosis in young boys). Terminal hematuria usually arises from the posterior urethra, bladder neck, or trigone. Among the common causes are posterior urethritis and polyps and tumors of the vesical neck.

Total hematuria has its source at or above the level of the bladder (eg, stone, tumor, tuberculosis, nephritis).

Unusual Consequences of Micturition

Postmicturition syncope has been observed occa­sionally in men. Orthostatic hypotension and cardiac standstill have been observed in one patient. Psycho-motor epilepsy and angina pectoris may be triggered by voiding.

 

COMPLAINTS RELATED TO SEXUAL PROBLEMS

         

 

Many people suffer from genitourinary com­plaints on a purely psychologic or emotional basis. In others, organic symptoms may be increased in severity because of tension states. It is therefore important to seek clues that might give evidence of emotional stress.

In women, the relationship of the menses to ureteral pain or vesical complaints should be determined, although menstruation may exacerbate both organic and functional vesical and renal difficulties.

Many patients, particularly women, recognize that the state of their ' 'nerves'' has a direct effect on their symptoms. They often realize that their "cys­titis" develops following a tension-producing or anxiety-producing episode in their personal or occupa­tional environment.

A. Sexual Difficulties in Men:

 

               

 

 

Men may com­plain directly of sexual difficulty. However, they are often so ashamed of loss of sexual power that they cannot admit it even to a physician. In such cases they may ask for "prostate treatment" and hope that the physician will understand that they have sexual com­plaints and that they will be treated accordingly. The main sexual symptoms include impaired quality of erection, premature loss of erection, absence of ejaculate with orgasm, premature ejaculation, and even loss of desire. Since these symptoms are usually of psychologic origin, this area must therefore be explored.

B. Sexual Difficulties in Women: Women suf­fering from the psychosomatic cystitis syndrome al­most always admit to an unhappy sex life. They notice that frequency or vaginal-urethral pain often occurs on the day following the incomplete sexual act. Many of then recognize the inadequacy of their sexual experi­ences as one of the underlying causes of urologic complaints; too frequently, however, the physician either does not ask them pertinent questions or, if patients volunteer this information, ignores it.

C. Sexual Difficulties of Suspected Psycho­somatic Origin: In treating sexual difficulties of sus­pected psychosomatic origin, the physician should explore pertinent facts concerning childhood, adoles­cence (sex education and experiences), marriage prob­lems, and relationships with relatives, business as­sociates, etc. Even when psychosomatic disease is strongly suspected before hi story-taking has been completed, a thorough examination and laboratory survey must be done. Both psyche and soma may be involved, and the patient must be assured that there is no serious organic disease. Although sexual interest and activity decline with advancing years, physically healthy men and women may continue to be sexually active into their eighth or ninth decades.

 

 

 

 

 

Instrumental Examination of the Urinary Tract

 

 

PRELIMINARY PROCEDURES

Aseptic Technique

Although bacteria are present in the distal urethra, the urinary tract is considered sterile. Therefore, any instrument entering the tract should be sterile. Instru­ments made of metal, rubber, and plastic may be autoclaved, but those containing optical devices must be gas-sterilized or soaked for a sufficient time in an approved solution of glutaraldehyde and then thor­oughly rinsed in sterile water.

The foreskin should be retracted and the glans penis washed thoroughly with cleansing solution. The vulva must be cleansed and the labia held apart as the instrument is introduced.

Lubrication of Urethra

 

                    Instrumental Examination

 

All transurethral maneuvers require lubrication. In women, application of lubricant to the instrument is sufficient. However, this method does not provide adequate lubrication for the entire male urethra, be­cause the meatus tends to remove most of the lubricant as the instrument is passed. The male urethra should be lubricated by instilling at least 15 mL of a sterile, water-soluble lubricant by means of a blunt, conetipped syringe. Oils (eg, mineral or olive oil) must not be used, since fatal oil emboli may result. The syringe allows introduction of the lubricant with constant, low, steady pressure, which helps overcome the normal tone of the external sphincter. This resistance may be markedly increased in apprehensive patients, leading the inexperienced instrumentalist to an erroneous diagnosis of urethral stricture.

Anesthesia

A simple procedure such as passage of a urethral catheter may be done without anesthesia. If more com­plex or painful manipulations are planned, sedation or topical, regional, or general anesthesia will be neces­sary.

Sedation may be achieved with barbiturates, tranquilizing agents, or narcotics.

Topical anesthesia of the urethral mucosa may be obtained with cocaine, tetracaine, or lidocaine. In females, a cotton applicator moistened with the anesthetic may be placed in the urethra for 5 minutes.

In males, these agents in liquid form are rapidly ab­sorbed into the circulation through the posterior ure­thra. Contact with traumatized mucosa or injection under pressure increases the absorption. This can lead to seizures, circulatory collapse, and cardiopulmonary arrest. Dyclonine,0.5% has been used without toxicity in males. Wherever these drugs are used as topical anesthetics for the urethra, resuscitation equipment should be available.

Lidocaine as a 2% solution in carboxymethylcel-lulose gel provides lubrication as well as safe topical anesthesia. The drug is less readily absorbed in this form and can be used in both the male and female urethra. In females, approximately 3-5 mL of the jelly is instilled into the urethra. To occlude the meatus, a cotton swab lubricated with jelly may be placed in the distal urethra or a sponge may be placed in the distal vagina. In males, 15-30 mL of the jelly is instilled 5-10 minutes prior to the procedure; a penile clamp is placed at the corona; and a small amount of jelly is instilled in the distal urethra. Topical anesthesia is effective on the mucosa only and will not prevent pain from pressure or from distortion of underlying struc­tures during manipulation.

Regional or general anesthesia should be planned if more painful procedures (eg, resection or biopsy) are contemplated or if the patient is very apprehensive. The regional anesthetic must reach the third lumbar segment to provide the necessary sensory ablation dur­ing transurethral resection; thus, spinal or epidural anesthesia rather than a sacral block must be used. General anesthesia must be used when cystourethroscopy is done in pediatric patients.

Warning to Patient

Instrumentation is uncomfortable and may be painful. A forewarned, cooperative patient will be of help. Explaining the proposed maneuvers as one pro­ceeds may reduce the patient's anxiety. The instrument must be introduced gently and advanced gradually. Gentle, sure maneuvering with adequate lubrication is essential. No movement should be rough or abrupt. Discomfort will increase as the instrument passes through the prostatic urethra, and men must be warned to anticipate some discomfort as this area is ap­proached. Once spasm of the external sphincter develops, it may be impossible to complete the in­strumentation. A very high bladder neck will cause marked angulation of the urethra that may preclude instrumentation under topical anesthesia.

Calibration & Size of Instruments

In the USA, instruments are most commonly cal­ibrated accQrding to the French (F) scale. Each number on the scale equals 0.33 mm. Therefore, a 30F sound has a diameter of 10 mm.

Each number on the American (A) and English (E) scales equals 0.5 mm; the English scale is 2 num­bers less than the American. Hence, 10 mm = 30F = 20A = 18E; and 6 mm = 18F = 12A = 10E.

THE CATHETER

Diagnostic uses of catheters include obtaining samples of urine for culture or microscopic examina­tion, detecting residual urine after voiding, and instil­ling contrast medium into the bladder. Catheters are used therapeutically to relieve urinary retention or to instill chemotherapeutic agents.

Types & Sizes of Catheters

In general, straight rubber catheters are used for routine diagnostic catheterization. However, a coude (elbow) catheter, which is stiffer and has a curved tip, may be more readily manipulated over an enlarged prostate that has elevated the bladder neck. Because its curve will help to avoid undermining the bladder neck, a coude catheter may be particularly useful if catheterization is necessary in the early postoperative period following transurethral resection of the prostate. A self-retaining Foley (balloon) catheter is used if the catheter is to be left indwelling.

 

  Types of Catheters

 

 

 A Malecot or Pezzer catheter may be left indwelling in females, but these catheters tend to slip out more readily and must be inserted with a stylet. It may be necessary or advan­tageous to leave a plain catheter (Robinson) in the bladder; in such cases, it must be taped in place. When clean intermittent catheterization is used to manage an atonic bladder, reusable short metal or plastic catheters are useful in females and longer plas­tic or rubber catheters in males.

 

 

   Foley (balloon) catheter

 

 

When a catheter is intended for prolonged use or an excessive amount of scarring is anticipated, it may be advantageous to use a catheter with silicone elas­tomer or a similar material bonded to its surfaces. These materials cause less tissue reaction and thus minimize catheter-induced trigonitis, urethritis, and meatitis. This is thought to be significant in reducing the incidence of urethral stricture in males. In addition, encrustation is reduced, which may allow longer inter­vals between changes of permanent indwelling cathe­ters.

A large whistle-tip catheter provides the best route for manual irrigation when a patient presents with clot retention. Once all clots are evacuated, a 3-way catheter provides channels for influx and efflux, so that continuous bladder irrigation is possible.

In general, it is a mistake to try to pass small catheters (12-14F) in men; a small catheter lacks body and is apt to coil up at the external sphincter. Catheteri­zation is really less traumatic and more successful if instruments of adequate size (20—22F) are used. How­ever, a plastic pediatric feeding tube (5F or 8F) may be helpful in catheterizing newborns or males with stric­tures. The urethra of a 6-year-old girl will easily accept a 14F catheter. The urethra of a boy of the same age will take a 12F catheter.

 

 

 

 

Technique of Catheterization 

    

                      Catheterization of the  bladder  

 

           

A. In Men: After proper cleansing and lubrica­tion, the catheter can be manipulated with a sterile-gloved hand. However, it may be simpler to grasp the catheter near its tip with a sterile clamp and hold the other end of the catheter between the fourth and fifth fingers of the same hand. The catheter can then be advanced with the clamp without being touched by the unsterile hand. Begin catheterization with the penis pointed slightly cephalad and drawn taut. When the increased resistance of the prostatic urethra is encountered, the taut penis is lowered and the cathe­ter gently advanced. If a balloon is to be used, the entire length of the catheter should be passed so that the balloon is not in the posterior urethra when it is in­flated.

 

 

 

 

 

If a stylet is used, the lumen of the catheter should be lubricated before the stylet is in­serted; otherwise, the stylet will be difficult to remove after passage of the instrument. The technique of pass­ing a catheter with a stylet is similar to that for passing sounds. The catheter should be drawn taut over the stylet so that its tip cannot become dislodged, pass oul through the "eye" of the catheter, and traumatize the urethra.

Do not partially withdraw the styleted catheter and then readvance it. The resulting drag on the cathe­ter may allow the tip of the stylet to protrude through the distal opening of the catheter and cause urethral injury. At times, it is helpful to guide stiff instruments with a finger in the rectum. When the catheter has been successfully passed, the stylet is removed.

 

      Passing metalic catheter

 

 

 

 

 

        Passing metalic catheter

 

 

If an impassable stricture is encountered, the ure­thra may be dilated with sounds or with filiforms and followers. In certain circumstances, it may be preferable not to dilate the urethra initially, because alternative forms of defini­tive treatment may be desirable once evaluation is completed. A feeding tube for premature infants may pass without dilatation of the urethra, or a percutane­ous suprapubic catheter may be inserted to relieve urinary retention.

B. In Women: A short metal or plastic catheter is more satisfactory than other types, since it can be manipulated with one hand while the other spreads the labia. Rubber catheters can also be used. Glass cathe­ters should not be used, because they easily develop small cracks and chips that can cause injury. A vaginal speculum may be useful to expose the meatus in women with an intravaginal meatus, and a finger placed in the vagina may help to prevent the catheter from slipping into the vagina. The firm, curved tip of a coude catheter may be useful in such cases. If an indwelling catheter is needed and only a single-lumen catheter is available, it may be taped to the shaved labial area and upper thigh or sewn to a labium.                                        

 

 

 

PERCUTANEOUS CYSTOSTOMY

 

Cystostomy is the general term for the surgical creation of an opening into the bladder; it may be a planned component of urologic surgery or an iatrogenic occurrence. Often, however, the term is used more narrowly to refer to suprapubic cystostomy or suprapubic catheterization. In a setting where an individual is unable to empty his or her bladder appropriately and urethral catheterization is either undesirable or impossible, suprapubic cystostomy offers an effective alternative.

 

Cystostomy for the purpose of suprapubic catheterization may be performed in 2 ways, as follows:

Via an open approach, in which a small infraumbilical incision is made above the pubic symphysis

Via a percutaneous approach, in which the catheter is inserted directly through the abdominal wall, above the pubic symphysis, with or without ultrasound guidance or visualization through flexible cystoscopy

 

A suprapubic catheter is useful in males when the urethra is impassable (eg, traumatic disruption or stric­ture), when there is epididymitis or severe urethritis, or when prolonged bladder drainage by means of an in­dwelling catheter is necessary. An indwelling urethral catheter predisposes to meatitis, urethritis, and epidid­ymitis.

The skin of the suprapubic area is prepared and infiltrated with a local anesthetic. If the patient is in urinary retention, the bladder is usually readily pal­pated. The bladder must usually contain a minimum of 200-300 mL of urine before a suprapubic catheter can be inserted successfully.

 

               

                                           PERCUTANEOUS CYSTOSTOMY  

 

  

                            

 

 

 

 

The patient may be placed in the Trendelenburg position to move the intestines cephalad. A thin lumbar puncture needle is inserted above the symphysis pubica and angled toward the perineum to locate the bladder. A trocar is inserted into the bladder and the suprapubic tube passed. Size 8F, 10F, and 12F su­prapubic catheters are available in prepackaged sets. However, larger sizes are usually needed for long-term drainage, and these may be placed initially through a much larger standard bladder trocar or after dilating an established suprapubic tract. In an emergency when appropriate urologic equipment is not available, a large-gauge central venous catheter of sufficient length can be used.

 

 

 

METAL SOUNDS

 

                 Technique of Passing a Sound

 

 

Metal (stainless steel or nickel-plated steel) sounds are used for urethral dilatation.

Technique of Passing a Sound

A. In Men: With the penis stretched taut and the instrument held almost horizontally (over the groin), the tip of the sound is introduced into the lubricated urethra. When the tip reaches the bulb (at the external sphincter), the handle is brought to the vertical posi­tion, which usually enables the tip to pass through the sphincter. Moving the handle to the horizontal position (parallel to the thighs) causes the sound to advance into the bladder.

The first sound passed should be a 24F, even though the patient says he has a narrow stricture. This size has a broad tip that will not perforate a friable urethral wall and is therefore ideal for urethral explora­tion. If a 24F sound cannot be passed, smaller sounds can be tried. If a 20F will not pass, do not use the smaller sizes, because their tips are relatively sharp and may pierce the urethral wall. In such cases, filiforms and followers may be used

B. In Women: Because of the short and rela­tively straight canal of the female urethra, the passage of sounds is quite simple in women. Significant stric­ture is rare.

FILIFORMS & FOLLOWERS

Filiforms and followers are instruments used to dilate narrow strictures. Hollow followers may be used to catheterize men with narrow strictures.

Types & Sizes

Filiforms have woven fiber cores with a coated surface; they are very pliable and smooth. Useful sizes are 3-6F. Numerous filiform tips are available, but the coude and corkscrew types are most useful. The free end of the filiform is equipped with a female thread.

The follower is made of metal or of woven pliable fiber. Useful sizes are 8-30F. A follower may be solid, or it may be hollow to allow simultaneous cathe-terization. Its end has a male thread that may be easily screwed into the filiform.

 

Technique of Passing Filiforms

After lubricant jelly has been instilled into the urethra, the filiform is introduced. If it is arrested, it must be partially withdrawn, rotated, and readvanced. If this fails, one or more filiforms should be added to the first and all manipulated in turn. When one finally passes down to its hilt without resistance, its tip has entered the bladder. The appropriate follower is then screwed into the filiform in a clockwise direction and advanced down the urethra. The follower must be passed carefully, because it is possi­ble to create a false urethral passage, particularly if the proximal filiform has coiled in the urethra.

When an indwelling catheter is required, the Councill stylet is a particularly useful follower. This may be attached to the filiform after appropriate se­quential dilatation of the urethra with woven follow­ers. An open-tipped indwelling catheter placed over the stylet is then passed into the bladder. Once the balloon is inflated, the filiform and stylet are removed.                              

 

               

 

BOUGIES A BOULE

These olive-tipped bougies are useful in calibrating the urethra. It is important to remember that calibration determines an anatomic measurement which may not correlate with physiologic urodynamic findings. Bougies of increasing size should be used until one passes with some resistance. On withdrawal, there will be a tug as the bougie's broad shoulders pass through the stenotic area.

 

 

 

CYSTOURETHROSCOPY

Instruments

Rapidly advancing technology has allowed con­tinued refinement of urologic endoscopic procedures. Older terminology differentiated a cystoscope from a panendoscope. The former instrument accepted a wide-angle lens that gave a view approximately at right angles to the shaft (ideal for the bladder), whereas the latter allowed a smaller field of vision nearly in line with the instrument (for the urethra). Modern cystourethroscopes have a metal sheath ranging in size from 8F to 26F and interchangeable fiberoptic tele­scopes allowing a view from 0 to 170 degrees. The 0-or 30-degree lenses are best for visualizing the urethra, whereas the bladder walls are best inspected with the 70-degree lens. A retrograde (170-degree) lens must be used to see the vesical side of the bladder neck, particularly where prostatic tissue obstructs the view. A flexible nephroscope passed through the urethra may help to visualize the area obscured by the bladder neck or the interior of an otherwise inaccessible bladder diverticulum.

 

Uses        CYSTOURETHROSCOPY

 

 

 

 

 

       CYSTOSCOPY

 

 

  

 

 

A. Diagnostic Uses: Complete endoscopic studies are among the most precise diagnostic tests in all medicine.

1. Direct inspection - The range of sheath sizes and the variety of telescopes available allow thorough visualization of the entire urethra and bladder. Any urethral lesions (eg, verrucae, tumors, strictures, and diverticula), as well as the size and configuration of the prostate and bladder neck, are noted before the bladder is inspected. When the bladder is entered, the trigone is visualized and the size, shape, position, and number of ureteral orifices noted. The bladder wall is carefully inspected for tumors, stones, diverticula, ulcers, trabeculation, hemorrhage, and edema. The normal and abnormal cystourethroscopic findings must be specifically described.

The bladder wall is dynamic, and as the bladder fills, small lesions will move away and may escape the examiner's field. Special care must be taken not to overdistend the bladder and to make sure that all areas have been completely inspected, often with the bladder minimally filled initially. In adults, most of the bladder wall cannot be seen if the bladder contains more than 200-300 mL of urine. Manual suprapubic pressure may be necessary in order to visualize the anterior bladder wall. The angle of the examining table should be adjusted to allow a clear view of the mucosa under­lying the air bubble. Biopsy specimens of suspicious areas are taken under direct vision with flexible or rigid biopsy forceps integrated with the cystourethroscope.

2. Urine specimens-Through the cystourethro­scope, separate samples can be obtained from the bladder and from the upper urinary tracts for bac-teriologic and cytologic study. To increase the cell yield, bladder washings for cytologic study are ob­tained by flushing a large syringe of saline back and forth through one of the instrument sheath's fluid ports. Similarly, when a ureteral catheter is passed to collect urine from the renal pelvis, gentle irrigation using a small amount of saline may increase the cell yield. These techniques may help to detect the source of abnormal cytologic findings when there are no ob­vious lesions on radiologic or cystoscopic examina­tion.

A minute brush held in a ureteral catheter sheath may be passed to a lesion in the ureter or renal pelvis in order to trap cells and small pieces of tissue for exami­nation.

B. Therapeutic Uses: Many diseases of the ure­thra, bladder, and lower ureter lend themselves to transurethral treatment. Once tumors have been biopsied (this should be done with cold-cup forceps to prevent cautery artifacts in the specimens), these le­sions may pefulgurated or resected.                        Basket

 

 Lower ureteral stones may be manipulated with various catheters to dilate the ureter or to entrap the stone in a stone basket for extraction. To relieve hydroureteronephrosis, indwelling ureteral stents may be placed transurethrally if they can be advanced up the ureter. It must be remembered that once these indwell­ing catheters are inserted, a foreign 6ody is in place, and a previously nonrefluxing ureter more than likely has been converted to a refluxing one.

 

Major Indications for Cystourethrography & Ureteral Catheterization

These techniques are utilized in the evaluation of hematuria, chronic or recurrent urinary infection, un­explained urologic symptoms (eg, enuresis, fre­quency), and evaluation of congenital anomalies. They are also useful in any clinical situation in which excretory urograms have suggested pathologic change but have not furnished all the information necessary for definitive diagnosis and treatment.

Contraindications to Cystourethroscopy

Cystourethroscopy is contraindicated in acute urinary tract infection, because trauma may exacerbate the infection and lead to sepsis. It is relatively con­traindicated in the presence of severe symptoms of prostatic obstruction, since trauma may produce just enough edema of the bladder neck to cause complete urinary retention. Of course, if cystoscopy is essential, this risk must be accepted.

 

 

NEEDLE BIOPSY OF THE PROSTATE

Various types of soft-tissue biopsy needles that remove cores of tissue from a suspicious area are available. In addition, needle aspiration to obtain specimens for cytologic examination is promising.

This biopsy is done by a doctor who specializes in men's genital and urinary problems (urologist) in the doctor's office, a day surgery clinic, or a hospital operating room.

Before your prostate biopsy, you may be given antibiotics to prevent infection. You may be asked to take off all of your clothes and put on a hospital gown.

 

 

 

 

 

 

Needle biopsy

 

 

The prostate may be approached via the perineal or transrectal route. After a local anesthetic is injected into the perineal skin, a finger in the rectum guides the tip of the needle (which is outside the rectal wall) to the suspicious area. The transrectal route does not require mucosal anesthesia but may be difficult to use in pa­tients with tight anal sphincters. An enema given be­fore the transrectal procedure is useful. It may be easier to biopsy small nodules via the transrectal route since the needle and the palpating finger are in direct con­tact. A needle biopsy may be done under general or spinal anesthesia in conjunction with cystoscopy.

If prostate cancer is suspected, a biopsy is recommended. A prostate needle biopsy is a surgical procedure in which a small sample of tissue is removed from the prostate gland and examined under the microscope by a pathologist, a doctor specializing in identifying disease through the study of cells, tissue and organs.

 The procedure takes about 15 minutes and is usually performed in the urologist's office in conjunction with transrectal ultrasound (TRUS), a procedure that uses sound waves to create a video image of the prostate gland. A local anesthetic is routinely used. With the help of TRUS, a doctor guides a biopsy gun — a hand-held device with a spring-loaded, slender needle — through the wall of the rectum into the area of the prostate gland that appears abnormal.

 

REACTIONS TO INSTRUMENTATION

Urethra & Bladder (Sounds, Cystoscopy)

Some bleeding is to be expected in men. Burning on urination and frequency may be noted because of trauma to the mucous membrane. Acute urinary reten­tion may develop in men suffering from moderate prostatism. This may be due to edema from the in­strumentation. Exacerbation of lower urinary tract in­fection may occur, particularly if there is residual urine. Epididymitis may develop if prostatocystitis is present. "Urethral chill" (bacteremia) may lead to septic complications and must be anticipated following instrumentation in the presence of an infected prostate or vesicoureteral reflux.

 

 

 

Ureters & Kidney

 

                Ureteral catheterization

 

(Ureteral Catheterization, Urography)

Ureteral catheterization may be performed with­out general or spinal anesthesia. However, nausea, vomiting, abdominal cramps, and back pain may occur from overdistention of the renal pelvis with contrast material or from edema secondary to trauma. If the catheter pierces the renal parenchyma, bleeding and clot colic may also ensue. Kidney infection may be exacerbated, or new infection may be introduced. Temporary anuria is rare; it may be caused by exces­sive ureteral edema from instrumentation in bilateral studies or by sensitivity to the urographic medium.

 

            

 

 

 

 

  X-Ray Imaging of the Urinary        Tract

 

Diagnostic imaging is a dynamic recent develop­ment in medical practice with great potential for bene­fiting patient care. Nothing has contributed more to the improvement of existing anatomic imaging devices and the development of new ones than digital com­puters and their related electronics. With computers, the vast numbers of data collected in analog fashion by the basic imaging mechanics of radiography, ultrasonography, computerized tomography (CT scan­ning), tomography are converted electron­ically into digits corresponding to the different inten­sities of the original bits of information. These digits are stored in the computer and can be recalled, com­bined, and manipulated in various ways to achieve reconverted analog images. Hard copies of selected images can be made at the time of the study, or the information can be stored permanently in digital form for subsequent retrieval and conversion to analog im­ages.

URORADIOGRAPHY

X-rays are electromagnetic waves with photon energies that fall between those of gamma rays and ultraviolet radiations in the electromagnetic spectrum. Radiography makes use of the fact that all substances and tissues differ in their ability to absorb x-rays pass­ing through them. A radiopaque contrast medium is frequently employed to help distinguish separate struc­tures and thus make radiograms easier to "read."

It is well known that improperly used x-rays can have harmful effects, particularly on the gonads and to fetuses early in gestation, but roentgenography is safe when properly used by trained personnel.        

Although newer imaging techniques are replacing radiography for diagnosis of some urologic problems, radiography remains the backbone of urologic prac­tice. It is often the first and sometimes the single most effective examination. Therefore, the urologist should be familiar with current x-ray equipment and uroradiologic techniques. The basic types of com­monly used uroradiologic studies are plain abdominal films, urograms, cystourethrograms, urethrograms, and angiograms. These studies and enhancement by radiographic subtraction are described separately be­low. Some uroradiologic studies widely used in the past, eg, retroperitoneal gas insufflation (for visualiza­tion of the adrenals and kidneys) and pelvic pneumography (for visualization of pelvic organs), have be­come obsolete.

Basic Equipment & Techniques

A. Equipment:

1. Radiography -The basic requirements for radiography are a high-voltage electrical source, an x-ray tube, x-ray film, and some type of film holder. In practice, film holders are built into a variety of upright stands, tables, and rapid film changers.

2. Fluoroscopy-Shortly after the discovery of x-rays, real-time radiographic imaging (fluoroscopy) was accomplished by direct viewing in a darkened room of the images produced by x-rays passing through the subject and striking radiosensitive fluores­cent screens.

 

 

3. Radiography-fluoroscopy (RF)-Modern x-ray units are vastly improved and much safer than the old ones and contain both radiographic and fluoro-scopic capabilities. RF units combined with an elec­tronic image intensifier and a television system are the mainstays of any diagnostic radiology department.

4. Image intensification-Radiographic image intensifiers came into use about 25 years ago and are now standard components of RF systems. Image inten­sifiers electronically augment the ordinary dim fluoro-scopic image so that it may be viewed in daylight. Most modem RF units with image intensifiers also have television cameras tied into the system so that the intensified picture can be recorded and relayed to a television monitor conveniently placed for viewing, either in the x-ray room or elsewhere.

5. Real-time radiographic image recording-Any single frame of the real-time electronically inten­sified fluoroscopic image can be recorded on "spot" x-ray film, or the continuing real-time image can be recorded on videotape to allow real-time replay or study of single frames.

6. Data transmission systems-Increasingly, radiographic and other anatomic images are being transmitted from the examination site to stations in the same building or to distant receivers, permitting clini­cians to examine the studies at locations apart from the imaging site.

B. Patient Preparation: It is no longer consid­ered necessary that patients be dehydrated in prepara­tion for urography. Indeed, dehydration is to be avoided in infants, debilitated and aged patients, and patients with diabetes mellitus, renal failure, multiple myeloma, or hyperuricemic states.

On the other hand, preliminary bowel cleansing is very desirable, although children under age 10 years usually need no bowel preparation for urography. Bowel preparation for a urogram should be no less conscientious than that required for a barium enema examination of the colon. There are many ways to obtain good bowel preparation, and the choice may be made according to individual preference.

C. Radiopaque Urographic Contrast Media: An important concept extensively exploited in diag­nostic radiology is that sharply contrasting and easily separable x-ray images can be produced by interfacing body tissues and structures with substances that are significantly different in radio-absorptivity. Such ra­diographic contrast media include liquids (almost all of which contain iodine), gels, solids (eg, barium prepa­rations), and gases (most commonly air, nitrous oxide, and carbon dioxide).

Some contrast media can only be administered by one route, which limits their usefulness for multisys­tem anatomic imaging. For example, barium is used almost exclusively for gastrointestinal x-ray studies. Others, eg, some water-soluble iodine-containing preparations, can be administered by several routes, including intravascularly, and can be used to study many organ systems. The latter type of medium is especially useful in urographic and angiographic x-ray studies.

D. Adverse Reactions to Urographic Contrast Media: All procedures utilizing intravascular contrast media carry a small but definite risk of adverse reac­tions. The overall incidence of adverse reactions is about 5%.

Most reactions are minor, eg, nausea, vomiting, hives, rash, or flushing, and usually require no treat­ment other than reassurance. However, cardiopulmo-nary and anaphylactic reactions can occur with little or no warning and can be life-threatening or fatal. Ac­cording to various reports, the incidence of death due to intravascular injection of contrast media ranges from 1 per 10,000 to 1 per 70,000, with most recent reports indicating a mortality rate of about 1 per 40,000.

Subjects with a history of allergies have a some­what higher incidence of reactions to intravenous con­trast media. There are no reliable methods for pretesting patients for possible adverse reactions. Therefore, the risks and benefits of using intravascular urographic contrast media should be carefully evaluated be­forehand for each patient.

Treatment of adverse reactions involves the use of antihistamines, epinephrine, vascular volume expan­ders, and cardiopulmonary drugs as well as ancillary treatment procedures indicated by the nature and se­verity of the reaction.

In some cases, imaging techniques not requiring contrast media are inadequate and examination using intravascular contrast media is absolutely critical even though the patient has a history of severe reaction to such media. Such patients have been given corticoste-roids in an effort to prevent recurrence of the untoward response. This preventive treatment is not always suc­cessful, however, and as yet there are no published data on large controlled series to indicate conclusively that prophylactic use of corticosteroids is effective for this purpose.

Advantages & Disadvantages

Radiography produces excellent anatomic images of almost any body part. Costs of equipment and exam­inations are moderate compared to those of some other imaging systems. Space requirements for ordinary ra­diographic equipment are not excessive, and sophisticated portable equipment is available for use in hospi­tal wards, operating rooms, and intensive care units. Because there are a great many specialists exclusively trained in radiography, its use is not confined to large medical centers. The major disadvantage of radiographic imaging is its fundamental basis in ionizing radiation.

1. PLAIN FILM OF THE ABDOMEN

      Plain film of the abdomen                                         

  

A plain film of the abdomen, frequently called a KUB (kidney-ureter-bladder) film, is the simplest uroradiologic study and the first performed in any radiographic examination of the abdomen or urinary tract. It is usually the preliminary radiogram in more extended radiologic examinations of the urinary tract, such as urography. It is usually taken with the patient supine, but when indicated, it may be taken with the patient in other positions. It may demonstrate abnor­malities in bones, adrenals, and other structures as well as giving information about the state of the kidneys and extrarenal urinary tract.

Because kidney outlines can usually be seen on the plain film of the abdomen (although they may be obscured if there is very little perirenal fat), the size, number, shape, and position of the kidneys can be determined. This contributes useful urologic informa­tion. For example, finding on a plain film symmetri­cally shrunken rather than enlarged kidneys in a patient with unexplained uremia would be useful in excluding surgically remediable bilateral urinary tract obstruc­tion as the cause of the renal failure.

The size of normal kidneys varies widely, not only between like individuals but also with age, sex, and body stature. The long diameter of the kidney is the most widely used and most convenient radio-graphic measurement. The average adult kidney is about 12-14 cm long, and the left kidney is ordinarily slightly longer than the right one. In children over 2 years of age, the length of a normal kidney is approxi­mately equal to the distance from the top of the first to the bottom of the fourth lumbar vertebral body. In adults, the length of a normal kidney is approximately 3-4.5 times the height of the second lumbar vertebra.

Identification on the plain film of calcification or calculi anywhere in the urinary tract may help to identify specific kidney diseases (eg, the calcifications occasionally seen in a kidney cancer) or may suggest primary disease elsewhere (eg, the occasional patient with nephrocalcinosis whose under­lying primary disease is hyperparathyroidism).

2. UROGRAPHY

The collecting structures of the kidneys, ureters, and bladder can be demonstrated radiologically by the following methods.

 

Excretory Urograms

 

             

         Excretory urogram  

 

 

 

                                       

The excretory urogram, formerly called an intravenous pyelogram (IVP), is most commonly used. Excretory urograms can demonstrate a wide va­riety of urinary tract lesions, are simple to perform, and are well tolerated by most patients. Occasionally, however, retrograde urograms (see below) may be required if the excretory urogram is unsatisfactory or the patient has a history of significant adverse reaction to intravascular contrast media. The advent of excretory urography using high volumes of radiopaque contrast media and ureteral compression(see below) has decreased the need for retrograde uro­grams.

 

 

A. Standard Technique: Following a prelimi­nary plain film of the abdomen, radiograms of the abdomen are taken at timed intervals after the intra­venous injection of a suitable iodine-containing radiopaque contrast medium. Such substances are promptly excreted by normal kidneys, almost entirely by glomerular filtration.

The volume and speed of injection of the radio-graphic contrast medium (rapid bolus, slow infusion, etc), as well as the number and type of films taken following injection, vary depending upon the institu­tion at which the studies are performed and the pa­tient's age, physical condition, and clinical problem. Several modifications of the standard technique have improved the study generally or increased its value in particular diseases.

 

B. High-Volume Technique: In most patients, use of standard intravenous radiopaque medium in the amount recommended by the manufacturer will usu­ally result in satisfactory diagnostic urograms. The amount of iodine commonly used in patients with normal renal function is approximately 300 mg/kg body weight. The use of greater than average amounts of standard contrast medium—and thus greater amounts of iodine per kilogram of body weight—may be indicated in selected patients. The high volumes may be injected either rapidly as a bolus or more slowly as an infusion; the bolus method produces bet­ter visualization and a better urographic nephrogram than the infusion method.

 

C. Rapid-Sequence ("Hypertensive") Tech­nique: This modification of the standard excretory urogram was devised to make the study more useful in the diagnosis of renovascular hypertension. In this method, the procedure for the standard intravenous urogram is altered to include several radiograms taken at intervals during the first few minutes after bolus injection of the contrast medium. This technique has increased somewhat the diagnostic value of the ordi­nary urogram in patients suspected of having renal-artery occlusive disease without prolonging the study or adding appreciably to its cost.

The rapid-sequence radiograms are examined for findings that could indicate renal artery stenosis, eg, significant differences in the size of the 2 kidneys or delayed appearance of the contrast medium, with later hyperconcentration in one kidney.

This rapid-sequence study was popular for years, but it is now agreed that it is at best only minimally effective as a screening study for suspected renovascu­lar hypertension.

 

D. Other Techniques: Additional modifications of the standard excretory urogram can be used. Radiographic tomography, x-ray imaging of a selected plane in the body, permits recognition of kidney structures that otherwise are obscured on standard radiograms by extrarenal shadows, eg, those due to bone or feces. Image-intensified fluoroscopy penmils real-time study of urinary tract dynamics. "Immediate" films, which are taken directly after the rapid (bolus) injection of contrast medium, almost always show a dense nephrogram and permit better visualization of renal outlines. Abdominal (ureteral) compression devices that temporarily obstruct the upper urinary tracts during excretory urograms dra­matically improve the filling of renal collecting struc­tures. "Delayed" films, which are taken later on the same day or on the day after the contrast medium is administered, often contribute useful urologic infor­mation. "Upright" films, taken with the patient standing or partially erect, reveal the degree of mobility and drainage of the kidneys and, if taken im­mediately after the patient has voided ("post-voiding" film), show any residual urine in the blad­der.

Retrograde Urograms                     

 

 

                                   Retrograde pyelography

 

Retrograde urography is a moderately invasive procedure that requires cystoscopy and the placement of catheters in the ureters. A radiopaque contrast medium is introduced into the ureters or renal collect­ing structures through the ureteral catheters, and radiograms of the abdomen are then taken. The study, which is more difficult than an excretory urogram, must be performed by a urologist. Some type of local or general anesthesia must be used, and the procedure can occasionally cause later morbid­ity or urinary tract infection.

 

 

                   

                              Retrograde pyelography

 

 Retrograde pyelography

 

 

 

   Retrograde pneumopyelography

    Retrograde pneumopyelography

 

Retrograde urograms may be necessary if excre­tory urograms are unsatisfactory, if the patient has a history of adverse reaction to intravenous contrast media, or if other methods of imaging are unavailable or inappropriate.

 

 

 

Percutaneous Antegrade Urograms

 

                 Percutaneous  Urograms

 

This method of outlining the renal collecting structures and ureters is occasionally used when uri­nary tract imaging is necessary but excretory or ret­rograde urography has failed or is contraindicated or when there is a nephrostomy tube in place and delinea­tion of the collecting system of the upper urinary tract is desired. The contrast medium is introduced either through nephrostomy tubes, if these are present (nephrostogram), or by direct injection into the renal collecting structures via a percutaneous puncture through the patient's back.

 

  

 

percutaneous puncture through the patient's back

 

Percutaneous Retrograde Urograms

These studies of the upper urinary tract are made by retrograde injection of contrast medium through the opening of a skin ureterostomy or pyelostomy (skin ureterogram, skin urogram) or through the ostium of an interposed conduit, usually a segment of small bowel ("loopogram ").

3. CYSTOGRAPHY & VOIDING CYSTOURETHROGRAPHY

A cystogram is a radiogram showing radiopaque outlining of the bladder cavity. Cystograms are seen as part of ordinary excretory urograms, but direct radiographic cystograms can be obtained by instilling a radiopaque fluid directly into the bladder.

 

       Retrograde cystogram

 

The contrast medium is usually instilled via a transurethral catheter, but when necessary, it can be administered via per­cutaneous suprapubic bladder puncture. Radiograms of the filled bladder are taken using standard overhead x-ray tube equipment, or less frequently, "spot" films are taken during real-time, direct, image-intensified fluoroscop.Voiding cystourethrograms are radiograms of the bladder and urethra obtained during micturition.

 

       Retrograde pneumocystogram

 

In addition to their use in imaging the bladder and urethra, cystography and cystourethrography are im­portant radiologic techniques for detecting vesicoureteral reflux and are the bases of several radiographic methods used in the workup of patients with urinary stress incontinence.

 

 

             Retrograde polycystogram

 

4. URETHROGRAPHY

The urethra can be imaged radiographically by retrograde injection of radiopaque fluid or in antegrade fashion with voiding cystourethrography.

 

       Retrograde urethrocystogrphy

                       

                            Retrograde urethrocystogrphy

 

 

 

 

Retrograde urethrocystogrphy

 

 

 

The antegrade technique is required when lesions of the poste­rior urethra, eg, posterior urethral valves, are sus­pected; the retrograde technique is more useful for examining the anterior urethra. An antegrade urethrogram can also be obtained by taking radiograms as the patient voids at the termination of an excretory urogram, when the bladder is filled with contrast medium.

 

 

 

5. ANGIOGRAPHY

Angiography is visualization of blood vessels by use of radiopaque contrast media. Angiographic study of the urinary tract is almost exclusively used to vis­ualize renal structures. Vesical angiography and penile angiography are seldom performed and of limited value.

 

               Angiography

 

 Although angiography is an established imag­ing technique with proved value and an acceptable incidence of complications and morbidity, it is moder­ately invasive and relatively expensive and usually requires a hospital stay. Increasing use of sonography, CT scanning, and digital angiography (see below) has resulted in a decrease in the use of angiography for diagnosis of urologic problems.

 

 

Aortorenal & Selective Renal Arteriography

 

           Selective      Renal Arteriography

 

Arteriographic study of the kidneys is performed almost exclusively by percutaneous needle puncture and catheterization of the common femoral arteries or, much less often, the axillary arteries. Rapid serial radiograms are obtained during and after bolus injec­tion of suitable radiopaque contrast medium into the aorta at the level of the renal arteries (aortorenal arteriogram, "flush" abdominal aortogram) or into one of the renal arteries (selective renal arteriogram).

 

 

In urologic practice, aortograms and renal arteriograms are most often performed to investigate renal tumors or renovascular lesions, to obtain vascu­lar maps before surgery is performed, or to evaluate the suitability of potential kidney donors.

Adenocarcinomas of the kidney usually have ob­vious abnormal vessels and are generally hypervascular, whereas transitional cell carcinomas are notoriously poorly vascularized and difficult to iden­tify by angiography. Renal hamartomas are often in­distinguishable from adenocarcinomas on angiog­raphy, but their fat content readily distinguishes them from adenocarcinomas on CT scans.

Benign renal cysts are avascular, with displace­ment of normal vessels around the sharply outlined cysts. Renal abscesses can mimic renal cysts on an­giography, although hyperemic inflammatory vessels may be visible around an abscess.

Although CT scans readily demonstrate the na­ture and extent of most renal tumors, many surgeons obtain abdominal and renal angiograms as vascular maps in order to determine the vascular limits of tumors, their degree of hypervascularity, whether they have other blood supplies in addition to the renal ar­teries, and whether renal vein tumor thrombi are pres­ent.

Inferior Venacavography & Selective Renal Venography

The common femoral veins are the usual site for catheterization and injection of contrast medium to visualize the inferior vena cava and renal veins.

 

   Inferior venacavography

 

    

 

Inferior venacavography is ineffective for demonstration of small paracaval masses or minimally enlarged retroperitoneal lymph nodes, but it can show lesions large enough to obstruct, distort, or displace the vena cava. It is useful to demon­strate extension of thrombus or tumor from renal veins into the vena cava. Renal vein tumor or thrombus that does not extend into the vena cava will not be evident on inferior venacavograms but can be visualized by selective renal venography.

Sonography and CT scanning are being used in­creasingly for visualization of abnormalities in the inferior vena cava and main renal veins.

Adrenal Angiography

 

 

Adrenal angiograms are not often performed. They are technically difficult because the multiple arteries supplying the adrenals are small and the adre­nal veins are difficut to catheterize selectively. In addi­tion, selective adrenal venography is not without hazard; the veins in the glands are particularly suscep­tible to rupture, and serious injury to the gland has resulted from intravasation of contrast medium into the adrenal parenchyma.

The need for adrenal angiography has been re­duced because sonography, CT scanning, and magne­tic resonance tomography are increasingly effective for adrenal imaging.

Miscellaneous Urologic Angiography

Although angiography has little or no value in examination of the ureter, bladder, and prostate, an­giograms of these structures may be indicated in par­ticular clinical situations, in which case the studies are usually "tailored" to the clinical problem.

Corpus cavernosograms are made by direct injec­tion of suitable contrast material into the corpora cavernosa of the penis. They can be useful in examin­ing for Peyronie's disease, impotence, priapism, and traumatic penile lesions but are not commonly per­formed.

 

6. RADIOGRAPHIC SUBTRACTION

Images of all body structures through which x-rays have passed are included in conventional radio­grams, with the result that images of structures of little or no interest are invariably superimposed on and obscuring those of clinical importance. Radiographic subtraction is a technique for removing (subtracting) unwanted shadows on the radiogram, leaving only the images of pertinent structures.

Until recently, radiographic subtraction has been a time-consuming manual process. Com­puterized image subtraction has now been incorpo­rated into radiographic systems. Such systems include image intensifiers and digital computers that electroni­cally convert the information in the intensified images into digits which are automatically compared, sub­tracted, and reformatted to display a subtracted image for immediate inspection.

At present, computerized radiographic subtraction is used almost exclusively in angiographic studies (digital angiography). With computerized radiographic subtraction equipment, it is possible to obtain satisfactory arteriograms of larger vessels, eg, the aorta, extracranial carotid arteries, and main renal ar­teries, with intravenous injection of radiopaque con­trast medium and thus avoid the more invasive proce­dures involving arterial punctures and catheterization. Other radiographic subtraction systems now being developed (energy-selective radiography) have the potential to make radiographic subtraction possible in all radiographic studies. For example, use of dualenergy radiographic systems will permit selective sub­traction of obscuring shadows due to bowel gas or bone from excretory urograms, leaving only unobscured urographic images.

 

 

SONOGRAPHY

Basic Principles                                                     

Sound is the propagation of a cyclic vibratory motion through a deformable medium. Sound is not an electromagnetic wave and, unlike x-rays, radiowaves, or visible light, cannot travel through a vacuum. A wave frequency of one cycle per second (cps) is called a hertz (Hz). Sound frequencies greater than 20 kHz are beyond the range of human hearing and are called ultrasound. Medical sonography uses ultrasound ap­paratuses to produce body images. The frequencies commonly used in medical sonography are 2.25, 3.5, and 5 MHz.

Ultrasound waves for imaging are generated by transducers, devices that convert electrical energy to sound energy and vice versa. These transducers are special piezoelectric crystals that emit ultrasound waves when they are deformed as an electrical voltage is applied and, conversely, generate an electrical po­tential when struck by reflected sound waves. Thus, they act as both sound transmitters and sound detec­tors. In imaging, repeated bursts of ultrasound from the transducer are transmitted through tissues. Be­tween transmissions, the transducer acts as a sound receiver.

Ultrasound imaging is based on the principle that acoustic energy is differentially attenuated by tissues of varying density, in somewhat the same way as x-rays are. But unlike radiograms, ultrasound images are reflection images formed when part of the sound that was emitted by the transducer bounces back from tissue interfaces to the transducer.

 

         T-r of the Kidney

 

 

 

     T-r of the Kidney

 

 

 

These reflected sounds vary in intensity and time according to the nature and location of the tissues from which they are reflected. In general concept, medical sonography re­sembles sonar.

The reflected sound energies are received by the transducer and converted into electrical signals that are amplified and stored in a computer. The information is converted by the computer into analog echo images of the acoustical profile of the tissues being examined. The images can be viewed directly in real time; permanently recorded on hard copy, film, or videotape; or both.

Clinical Sonographic Imaging

Sonography produces good images of the urinary tract and is being used increasingly as the initial screening procedure in sus­pected urinary tract disease, particularly when expo­sure to x-rays is undesirable or intravenous contrast medium is contraindicated.

 

    Tumor of the Bladder

 

The renal calices and central sinus tissues produce strong sonographic echoes; echoes from the renal pyramid are less intense; and those from the renal cortex are of intermediate strength—slightly less in­tense than those from the liver. Uncomplicated cysts and ordinary fluid-filled structures (eg, a distended bladder, a dilated ureter, or hydronephrosis) are anechoic, whereas renal tumors, complicated cysts, and abscesses produce echoes to varying degrees rang­ing from minimal to intense. Renal hamartomas are usually hyperechoic.

Sonography is the primary method of examining a fetus suspected of having major urinary tract disease, particularly obstructive disease. It is the method of choice in some cases and is excellent for examination of many types of urinary tract abnormalities, including congenital, acquired, obstructive, and nonobstructive lesions. It is useful in examination of kidneys not visualized by excretory urography, in renal transplant problems, and in scrotal diseases. It is very useful to determine localization for percutaneous aspiration and for biopsy.

Advantages & Disadvantages

The advantages of sonography are its safety, noninvasiveness, relative speed of performing tests, inexpensiveness, and flexibility. The equipment is rel­atively small in comparison with other imaging equipment and is mobile.The major disadvantages of sonography are that structures behind bones or bowel gas cannot be im­aged, special training is necessary for proper interpre­tation of sonograms, and a skilled operator is required.

 

 

CT SCANNING (COMPUTED BODY TOMOGRAPHY)

Basic Principles

 

 

 

 

  

 

 

In radiography, a broad beam of x-rays passes through the subject to produce an image on a detector, the x-ray film. In CT scanning, a thin, collimatedbeam of x-rays is passed through the subject, and the detector is some type of phototube or ionization chamber rather than x-ray film. CT scans give remarkable definition of body anatomy.

When scanning, the interconnected x-ray source and detector system is rapidly rotated in the gantry around the recumbent patient, the detectors recording a number of transmitted x-rays during the very short scan period. Digital computers assemble and integrate the collected information as directed by the operator at the CT console. The information is finally reconstructed into a cross-sectional image (tomogram) that is displayed directly on a television screen. The image can be photographed, stored in digital form for later retrieval, or both. The newest CT scanners have scan­ning cycles of less than 2 seconds, and scanners with much shorter scanning times are being developed.

 

 

 

               

Clinicl CT
Scanning

Because collapsed or fluid-filled loops of bowel can mimic soft tissue masses on CT images, radiopaque contrast medium is administered orally or rectally at the time of the CT study to identify gastroin­testinal structures. Radiopaque contrast medium may also be injected intravascularly at the time of the scan to produce contrast delineation of the urinary tract and vascular structures (the so-called enhanced CT scan). Radiograms and CT scans are reflections of the amount of x-rays reaching the respective detectors after passing through body tissues. Tissues that absorb much of the x-ray beam, eg, bone, will appear as white (radiopaque) shadows on the CT scan, just as they do on conventional radiograms; tissues that absorb little photon energy, eg, fat and gas, record as black (radiolucent) shadows. Body tissues have their own individual radioattenuating values, denoted by CT numbers. Water has been assigned a CT number of 0; fat and gas have negative CT numbers; bone and metal have positive CT numbers; and soft tissues have various positive CT numbers greater than 0 (the CT number of water) but less than the CT number of bone. The value at any point on the CT scan can easily be determined by the CT apparatus.

 

 

The most eye-pleasing CT scans are in patients with large amounts of body fat, because the black CT image of fat throws the tissues and organs with higher CT numbers into sharp relief. Renal cysts have CT numbers close to that of water and lower than those of tumors, complicated cysts, and abscesses. An-giomyolipomas have negative CT numbers corre­sponding to their fat content.

Although CT scanning can be used to image all parts of the urinary tract, it is used almost exclusively for examination of the abdominal and pelvic urinary tract. CT scanning is effective for staging and follow­ing urologic tumors and for determining localization for percutaneous aspiration and biopsy. With the in­creasing use of CT scanning alone or combined with sonography, there has been a sharp decrease in the use of conventional and invasive radiographic studies of the urinary tract.

     Tumor of the Bludder

 

 

Advantages & Disadvantages

The advantages of CT scanning of the urinary tract are that it demonstrates organ morphology, par­ticularly of retroperitoneal structures, exceptionally well; is relatively easy to interpret without special training; and can be done on an outpatient basis.

Its disadvantages are its basis in ionizing radia­tion; the cost, size, and immobility of the equipment; and the cost of the studies, which are more expensive than sonography and most radiographic examinations.

 

 

Magnetic Resonance Imaging

 (MRI), nuclear magnetic resonance imaging (NMRI), or magnetic resonance tomography (MRT) is a medical imaging technique used in radiology to visualize internal structures of the body in detail. MRI makes use of the property of nuclear magnetic resonance (NMR) to image nuclei of atoms inside the body.

 

An MRI scanner is a device in which the patient lies within a large, powerful magnet where the magnetic field is used to align the magnetization of some atomic nuclei in the body, and radio frequency magnetic fields are applied to systematically alter the alignment of this magnetization. This causes the nuclei to produce a rotating magnetic field detectable by the scanner—and this information is recorded to construct an image of the scanned area of the body. Magnetic field gradients cause nuclei at different locations to precess at different speeds, which allows spatial information to be recovered using Fourier analysis of the measured signal. By using gradients in different directions, 2D images or 3D volumes can be obtained in any arbitrary orientation.

        

 

MRI provides good contrast between the different soft tissues of the body, which makes it especially useful in imaging the brain, muscles, the heart, and cancers compared with other medical imaging techniques such as computed tomography (CT) or X-rays. Unlike CT scans or traditional X-rays, MRI does not use ionizing radiation

 

 

 

MRI is short for Magnetic Resonance Imaging. It is a procedure used in hospitals to scan patients and determine the severity of certain injuries. An MRI machine uses a magnetic field and radio waves to create detailed images of the body. Common reasons people go in to get an M.R.I. are for a sprained ankle or back pain.

The exam itself takes about 30 - 45 minutes. However, this may vary depending on the number of body parts being examined.

A strong magnetic field is created by passing an electric current through the wire loops. While this is happening, other coils in the magnet send and receive radio waves. This triggers protons in the body to align themselves. Once aligned, radio waves are absorbed by the protons, which stimulate spinning. Energy is released after "exciting" the molecules, which in turn emits energy signals that are picked up by the coil. This information is then sent to a computer which processes all the signals and generates it into an image. The final product is a 3-D image representation of the area being examined.

Radionuclide Scans

A radionuclide scan is an imaging technique that relies on the detection of small amounts of radiation after injection of radioactive chemicals. Because the dose of the radioactive chemicals is small, the risk of causing damage to cells is low. Special cameras and computers are used to create images of the radioactive chemicals as they pass through the urinary tract. Radionuclide scans are performed at a health care provider’s office, outpatient center, or hospital by a specially trained technician, and the images are interpreted by a radiologist; anesthesia is not needed. Radioactive chemicals injected into the blood can provide information about kidney function. Radioactive chemicals can also be put into the fluids used to fill the bladder and urethra for x ray, MRI, and CT imaging.

 

 

 

References:

a) basic literature:

1. Donald R. Smith, M.D. General Urology, 11-th edition, 1984, p.1-148

2. Official Journal of the European Association of Urology /2002-2007/.

3. Urological Guidelines (European Assosiation of Urology) Health Care Office /august 2004 edition/.

5. O.F.Vozianov, O.V.Lyulko. Urology.- Kyiv: Vischa shkola, 1993, p.14-76

6. Urology edited by N.A.Lopatkin, Moscow, 1982, p.3-67

 

b) supplementary literature:

1. Urinary Tract Infection and Inflamation / Jackson E. Fowler, JR. MD. Year Book Medical Publishers, Chicago 1989, p. 1-13

2. European Urology Supplements /2002-2007/.

3. Scientific Foundations of Urology. Third Edition 1990. Edited by Geoffrey D. Chisholm and William R. Fair, MD. Heinemann Medical Books, Oxford., p.17-40

4. European Urology via www.eropeanurology.com

5. Urology The Gold Jounal /www.goldjournal/net/.